When to use primitive and when reference types in Java

Question

In which case should you use primitive types(int) or reference types (Integer)?

This question sparked my curiosity.

Answer 1

When we deal with Spring getRequest mapping methods, using boolean value does not work.

For instance :

@GetMapping("/goal")
public boolean isValidGoal() { 
    boolean isValid = true;
    return isValid;
}

Always opt for Boolean in those cases.